There have been many prior inventions concerning the better watering and/or feeding of plants in containers and also for the watering of cut flowers in a vase even for their limited times of enjoyment. By way of example, in 1932, Charles E. Reynolds in his U.S. Pat. No. 1,842,687, described how he automatically dispensed water from a container which was placed in a vase among cut flowers. The principle he utilized was: water will not flow from an airtight receptacle unless air is admitted thereto, then when a level of water in a vase or pot, ot other container drops to the bottom of an air tube depending from the receptacle, air is permitted to pass up into the receptacle, and water or other liquid is discharged from the tube or from other means, until the level of the water in the container raises again to cover the bottom of the air tube, thereby shutting off the flow of air and water and/or other liquid.
Also in 1969, Hermann Rohling in his U.S. Pat. No. 3,438,575 described his root controlled watering device utilizing this same principle in several other embodiments of apparatus, some of which were connected to irrigation supply systems to replenish the water tanks, i.e. the receptacle. In 1973, Gary G. Bates, in his U.S. Pat. No. 3,754,352, presented his device, for watering trees and plants, which delivered water to root locations, when the roots were soon to be dry, utilizing this same principle, wherein water was held in a receptacle until the water seal below ground level was broken, allowing air to reach the space above the water in the receptacle and eliminate the vacuum.
In 1974, Hermann Rohling presented another of his watering devices in his U.S. Pat. No. 3,856,205 centering his attention on the proper watering of potted plants using small size apparatus having no moving parts. Again he used the same principle. Over a period of time, the water evaporated from the soil and/or was absorbed by the roots of the plant. Thus the water level in the pot lowered below the bottom opened end of a tube, thereby allowing air to flow through the soil and into the tuve and subsequently into the container, i.e. receptacle. Thereby the vacuum was relieved, causing water to flow again, until a subsequent equilibrum was reached. Although Mr. Rohling's apparatus was small and had no moving parts, many especially formed components were assembled to complete the watering device.
In 1979, Donavan J. Allen in his U.S. Pat. No. 4,148,155, disclosed his system for automatically feeding plants, wherein he also utilized the same principle, wherein water and/or a plant food nutrient flows out of a receptacle, until the sufficient quantity of such liquid in the soil, seals off the bottom vent opening, i.e. bottom of an inserted tube. Mr. Donavan used bottles as his reservoirs or receptacles.
Although these prior inventions successfully utilized this principle to water plants on the demand of the lack of water in the locale of the roots, presently it is believed there is no widespread use of such inventions utilizing this principle. Those offered previously, for example, may have unwantedly had their below soil vents easily clogged by soil, which entered excessively and/or compactedly when their vented portions were inserted into the soil or moved around in the soil.